1. Field of the Invention
The present invention generally relates to controlling a gas in a group of gases produced from a reservoir and specifically relates to controlling the amount of methane gas in a group of gases produced from a reservoir.
Subterranean formations often contain desirable materials that can be used for many applications. Therefore, there is need to remove the desirable materials from the subterranean formation. The subterranean formations often extend horizontally over many thousands of feet and are often very shallow in depth.
Coal is a desirable material contained in a subterranean formation. Methane is also contained in the subterranean formation. When the coal is mined methane gas is released. After the coal is mined, air is introduced into the methane gas.
Wells are drilled into the subterranean formation to obtain the methane gas for commercial production. There can be hundreds of wells spread out through a mining formation.
The methane gas produced from the wells is sold to commercial energy suppliers. Each well is connected to a central pipeline that leads to the particular commercial energy supplier. The commercial energy supplier often requires that the gas produced and transferred in the central pipeline meet a certain BTU level or have a certain amount of methane gas.
Because air is introduced into the methane gas during the mining operations, the wells produce a group of gases. Sometimes the group of gases produced by the well does not meet the desired amount needed by the commercial energy supplier.
Initially when a well bore produces the methane content is high. However, over time the amount of methane in the group of gases can decrease.
2. Description of Related Art
Currently, well bores are manually checked by a person to determine the amount of methane being produced. If the amount of methane being produced by a particular well is not adequate then the well bore is closed. After a return visit, the well is checked and, if it can produce again at the proper level, the well is reopened. If the well is still not properly producing it may be permanently closed off. Because of the many well bores that the person has to visit, they probably are only able to check the well a maximum of once every three days. When a person checks a well they typically have to shut in the well to test it.
There is no other known method for controlling the amount of a specific gas in a group of gases produced from a well bore.
The object of this invention is to provide of method and apparatus for controlling the amount of methane gas in a group of gases produced from a given well bore.